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    <script>
      // 实现一个计数器函数，每次调用该函数返回一个递增的数字
      //实现以下效果

      const createCounter = () => {
        let count = 0
        function fn() {
          count++
          return count
        }
        return fn
      }
      const counter = createCounter()

      console.log(counter()) // 1
      console.log(counter()) // 2
      console.log(counter()) // 3
    </script>
  </body>
</html>
